On deflection routing in optical burst-switched networks

This paper investigates the performance of deflection routing in optical burst-switched networks adopting Just-Enough-Time (JET) signaling mechanism. In general, buffer requirement is not vital for JET-based optical burst switching (OBS). However, if deflection routing is enabled, optical buffers are indispensable to prevent data bursts from overtaking associated control packets. Another solution, which can alleviate buffering, is to lengthen offset time in the beginning. As previous work indicated, a burst with extra offset time has higher priority than that without extra offset time and quality-of-service (QoS) can be accomplished in this way. In this paper, we consider the performance of deflection routing in both non-prioritized and prioritized JET-based optical burst-switched networks. For each case, a variant of priority queuing model is proposed to approximate burst loss probability respectively and the results show that the model provides an accurate estimation. We also evaluate the performance of deflection routing with and without QoS support in arpanet-2 topology.